diff --git a/pie/data/dataset.py b/pie/data/dataset.py
index dee3b41..dc7b35b 100644
--- a/pie/data/dataset.py
+++ b/pie/data/dataset.py
@@ -248,8 +248,14 @@ def register_upper(self):
         if self.max_size:
             t = len(self.inverse_table)
             r = len(self.reserved)
-            if (self.max_size - t - r) > 0:
-                new_chars = new_chars[:min(len(new_chars), self.max_size-t-r)]
+            slots_left = self.max_size - t - r
+            if slots_left > 0:
+                new_chars = new_chars[:min(len(new_chars), slots_left)]
+                if slots_left < len(new_chars):
+                    logger.info(f"Could not register all available uppercase vocab entries "
+                                f"({slots_left} slots < {len(new_chars)} upper chars)")
+                else:
+                    logger.info(f"All uppercase ({self.name}) vocab registered ({len(new_chars)} new entries)")
             else:
                 return # We have too much in the vocab already